Hydraulic ratchet wrenches



United States Patent HYDRAULIC RATCHET WRENCHES Seymour Herbst and Melvyn H. Bergman, Riverdale, N. Y.

Application August 12, 1954, Serial No. 449,338

Claims. (Cl. 81-60) This invention relates to wrenches and particularly to improvements in hydraulically actuated ratchet wrenches.

An object of this invention is to provide an improved hydraulically actuated ratchet wrench for turning a bolt or nut where the access to such bolt or nut is relatively limited.

Another object of this invention is to provide a hydraulically actuated ratchet wrench which will be eiective for rotating a nut or bolt in either direction by merely turning over the wrench.

Other objects and advantages of this invention will become clear hereinafter as the characteristic features of construction and mode of operation of my novel hydraulic ratchet wrench are described in detail.

In the accompanying drawings:

Fig. 1 is a plan view of a hydraulic ratchet wrench embodying our invention having a portion of the housing cut away to more clearly illustrate the details of the wrench;

Fig. 2 is a side view of the wrench shown in Fig. l;

Fig. 3 is a sectional view taken along the line 3-3 of Fig. l;

Fig. 4 is a sectional View taken along the line 4 4 ot Fig. l; and

Fig. 5 is a sectional view taken along the line 5 5 of Fig. 1.

Like reference characters refer to like parts in each or" the several views.

Referrino now to the drawings in detail, the ratchet wrench 1G includes a tubular member 12 having dened therein a hollow portion or cylinder 14 consisting of a relatively wide part 16 and a relatively narrow part 1S. Cylinder 14 extends the entire length of member 12 and is open at both ends. Positioned in the wide portion 16 of cylinder 14 is a piston 20 which piston is of substantially the saine diameter as the wide part 16 and has a relatively liquid tight fit therewith. A cover 26 is threadedly engaged as at 28 with member 12 to provide a liquid tight joint. Cover 26 is provided at its center with an aperture 24 through which a piston rod 22 extends. Piston rod 22 is connected at one end to piston 2G and is connected at its other end between two plates 3l) which are suitably secured to each other. Pivotally mounted on cover 26 are two pairs of handles 32 and 34 which are movable from an open position in which the ends of the pairs of handles are relatively remote from one another, as shown in solid lines in Fig. l, to a position in which the handles are relatively close to one another, as shown in dotted lines in Fig. 1. Pivotally connected between each pair of handles 32 and 34 on pins 35 and 37, respectively are links 36 and 38, respectively, which links are pivotally mounted at their other ends on plates 30. Pins 35 and 37 connect each pair of handles together so that they move in unison. A helical spring wound around piston rod 22 extends between cover 26 and plates 30 and biases the handles 32 and 34 to their open position, shown in solid lines in Fig. l. When the handles are operated from their rice open to their closed positions, shown in dotted lines in Fig. l, the piston rod will move towards the left as viewed in Fig. 1, thereby moving the piston 28 from a position shown in solid lines therein to the position shown in dotted lines therein. During this movement spring 4i) is of course compressed. When the handles are released spring 40 will be effective for returning them to their open positions thereby returning the piston to its position shown in solid lines.

Connected to the other end of tubular member 12 is a head member 42 which is substantially disc like in contiguration. Head member 42 includes a main body part 43 a cover member 45 which is suitably secured thereto. It is within the scope of this invention to have the head member integral with the tubular member 12 but separate pieces suitably secured together have been found preferable from a manufacturing Viewpoint. Head member i2 is provided with a round arcuate channel 44 which channel is connected with narrow part 1S of the hollow portion 14 in tubular member 12 thereby providing for a continuous channel, Disposed in arcuate channel 44 is an arcuate plunger 46 which tits against the walls of the channel to provide a liquid tight t. A suitable liquid such as a commercial hydraulic oil iills the hollow portion 14 of tubular member 12 between the piston and the plunger so that when the piston is operated from the position shown in solid lines in Fig. 1 to the position shown in dotted line in Fig. l, the liquid will move to the left and thereby force arcuate plunger 46 from the position shown in solid lines in Fig. l to the posi* tion shown in dotted lines in Fig. 1. Connected to piston 2li by any suitable connecting means such as hook 43 is a cable Sti which cable is connected at its other end to one end of a helical spring 52, the other end of the spring being suitably secured to the adjacent end of arcuate plunger 45. Accordingly, when the handles are permitted to move from their closed or their open positions due to the bias of spring 49 the piston will move to the right and pull cable Sti with it thereby exerting a force through spring 52 to pull arcuate plunger 45 to the right. It will be seen that by operating piston 2i) in wide part 16 of hollow portion 14 and by positioning plunger 46 in narrow channel 44, a relatively small movement of piston 2t will result in a relatively large movement of plunger 46. However, our invention is not restricted to such proportioning of the parts.

Arcuate plunger 45 is provided at its end remote from spring 52 with a recess or depression 54 in which is disposed a biasing spring 56. Rotatably mounted in head end 42 in beveled bearings 57 and 59 is a ratchet wheel 58 having a plurality of beveled teeth 60. A pawl 62 is also disposed in recess 54 and engages biasing spring 56 which spring biases the pawl 62 into engagement with ratchet wheel 53. lt will be seen therefore that when the handles are moved toward their close position thereby moving piston 2i) to the left as viewed in Fig. l, the liquid in the hollow portion wiil move toward the left thereby forcing arcuate plunger 46 in an arcuate path in a clockwise direction and cause pawl 62 to engage one'of the teeth 60 of ratchet wheel 58 and thereby rotate the ratchet wheel in a clockwise direction. When the handles are returned to their open position the cable Sti through spring 52 will return arcuate plunger 46 to its position shown in solid lines in Fig. 1 and pawl 62 will ride along the beveled edges or" the teeth. 60 and move into the recess against the bias of spring 56, either the friction of the parts, the resistance to rotation of the -nut or bolt, or both preventing the ratchet wheel from turning in the counterclockwise direction, Accordingly,`on the return stroke there will be no counterclockwise movement of ratchet wheel 58. Y

Positioned in a square aperture 64 in ratchet wheel 58 is a socket 66 which socket is movable longitudinally and will be held in the position shown in Fig. 2 by spring biased ball 63 cooperating with an indentation 7l) on the wall of the socket 66. Since both the socket 66 and the apertures 64 are square there will be no relative rotation therebetween so that when the ratchet wheel rotates in its clockwise direction, socket 66 will rotate in its cloc f.- wisedirection. Furthermore, if it is desired to operate socket 66 inra counterclocliwise direction all that need be done is to force socket 66 downward, as viewed in Fig. 2, so that ball 68 will ride out of indentation and move the socket longitudinally until ball 68 moves into indentation 72, to thereby position the socket as shown in dotted lines in Fig. 2. lt will be seen that if the tool is thereafter turned over, the direction of rotation of the socket will be counterclockwise amd,4 accordinflv, a'reverse action may be achieved. Furthermore, if it. is desired, socket 66 can be completely removed from aperture 64 and replaced with another socket having the same outer dimensions but different inner dimensions in order to tit nuts and bolts of different sizes.

In using our novel wrench, we have found that it there isroom for at least partial rotation of the entire wrench, the rotation of the wrench is adcitive with the rotation of the arcuate plunger so that a nut or bolt may be tightened or loosened more quickly by superposing both rotationsthan by employing the rotation imparted to the socket by the arcuate plunger alone.

Although we have herein shown and described only one form of our invention, various changes and modifications may be made therein within the scope of the appended claims without departing from the spirit and scope of our invention.

Having thus described our invention, what we claim and desire to secure by Letters Patent is:

l. A hydraulic ratchet wrench comprising a tubular member, a liquid in the hollow portion of said tubular member, piston means operatively connected to said tubular member forapplying pressure to said liquid, an end member having an arcuate channel detined therein, said end member being operatively connected to said tubular member so that said channel is connected to the hollow portion of saidV tubular member whereby when said piston means applies pressure to said liquid, a portion of said liquid enters said channel, an arcuate plunger s disposed in said channel and movable in response to the ow of liquid in said channel, and ratchet means associated with said arcuate plunger and operable when said plunger is moved by the ow of said liquid.

2. A hydraulic ratchet wrench comprising a tubular .A1

member, a liquid in the hollow portion or" said tubular member, piston means operatively connected to Ysaid tubular member for applying pressure to said liquid, an end member having an arcuate channel deined therei. said endmember being operatively connected to said tubular member so that said channel is connected to the hollow portion of said tubular member whereby when said piston means applies pressure to said liquid, a portion of said liquid enters said channel, an arcuate plunger disposed in said channel and movable in response to the liow of liquid in said channel, a pawl operatively connected to said arcuate plunger and movable therewith,

Y and a ratchet wheel rotatably mounted in said end member and engageable by said pawl so that when said liquid flows in response to operation or said piston means, said arcuate plunger and pawl Vwill move and thereby rotate said ratchet wheel.

3. A hydraulic ratchet wrench comprising a tubular member, a liquid in the hollow portion of said tubular member, piston means operatively connected to said tubular member for applying pressure to said liquid, an end member having an arcuate channel defined therein, said end member being operatively connected to said tubular member so that said channel. is connected to the hollow portion of said tubular member whereby when said piston means applies pressure to said liquid, a portion of said' liquid enters `said channel, an arcuate plunger 4. A hydraulic ratchet wrench comprising a tubularV member, the hollow portion of said tubular member having parts ofrelatively large and small cross-sections, piston means disposed within said large cross-sectional part o'r said hollow portion and operable between tirst and second conditions, an end member having an arcuate channel defined therein, said end member beingV operatively connected to said tubular Vmember so that said channel is connected to the small cross-sectional partY of said hollow portion,'an arcuate plunger disposed within said arcuate channel, and movable between lirst and second positions, a liquid in said hollow portion between said piston means and said arcuate plunger so 'that when said piston means is operated from its irst to its second condition said arcuate plunger moves from said r'irst to said second condition, and a work member operatively mounted on said end member for rotation and operatively connected to said arcuate plunger and rotatable in response to movement ot" said arcuate plunger from said lirst to said second condition.

5. A hydraulic ratc et wrench comprising a tubular member, the hollow portion of said'tubular member having parts of relatively large and small cross-sections, piston means disposed within said large cross-sectional part.

of said hollowI portion andoperable between first and second conditions, an end member having an arcuate channel denne-:l therein, said end member being operatively connected to said tubular member so that said channel is conne-:ted to the small cross-sectional part oi said hollow portion, an arcuate plunger disposed within said arcuate channel, and movable between lirst and second positions, a liquid in said hollow portion between said piston means and said arcuate plunger so that when said piston means is operated from its lirst to its second condition said arcuate plunger moves from said first to said second condition, a pawl operatively connected to said arcuate plunger and movable therewith, and a ratchet wheel rotatably mounted in said end member and engageable by said pawl so that when said liquid flows in response to operation of said piston means, said arcuate plunger and pawl will move and thereby rotate said ratchet wheel, and a working member operatively connected to said ratchet wheel for rotation therewith.

6. In a ratchet wrench having a tubular member t lin liquid in the hollow portion thereof and piston means disposed irt said hollow portion for imparting movement to the liquid, said wrenchY being further provided with'an end rnember operatively connected to said tubular member andhaving rotatably mounted Vthereon a working member, that improvement which comprises providingl the end member with an arcuate channel having an end in registry with an end o the hollow portion of said tubular member so that when said piston means is operated said liquid will ow into said channel, an arcuate K plunger disposed within said channel and movable in response to the iiow of liquid therein, and ratchet means operatively connecting said arcuate plunger and said working member for imparting rotary movement to said working member when said Varcuate plunger moves in respouse to the ow of said liquid.

7. A hydraulic ratchet wrench comprising a tubular member, a piston disposed within the hollow portion of said tubular member adjacent one end thereof and movable between first and second positions, means for moving said piston, an end member operatively connected to said tubular member and being provided with an arcuate channel having an end in registry with the other end of said hollow portion, an arcuate plunger disposed in said arcuate channel and movable between first and second positions, liquid in said hollow portion for moving said arcuate plunger from said rst to said second position when said piston is moved from said first to said second position, a cable operatively secured at one end to said piston and operatively secured at its other end to said arcuate plunger for moving said arcuate plunger from said second position to said first position when said piston is moved from said second to said first position, a working member rotatably mounted on said end member, and ratchet means operatively connecting said arcuate plunger to said working member for rotatably moving said working member when said arcuate plunger is moved from said first to said second position.

8. A hydraulic ratchet wrench comprising a tubular member, a piston disposed Within the hollow portion of said tubular member adjacent one end thereotC and movable between tirst and second positions, means for moving said piston, an end member operatively connected to said tubvl member and being provided with an arcuate channel having an end in registry with the other end of said hollow' portion, an arcuate plunger disposed in said arcuate channel and movable between first and second positions, liquid in said hollow portion for moving said arcuate pli rom said first to said second position when sa,c piston is moved from said first to said second position, a cable operatively secured at one end to said piston and operatively secured at its other end to said arcuate plunger for moving said arcuate plunger from said second position to said first position when said piston is moved from said second to said Airst position, o ratchet wheel rotatably mounted on said end member, a pawl operatively connected to said arcuate plunger and extending outwardly therefrom toward said ratchet Wheel, spring operatively engaging said arcuate plunger and pawl for biasing said pawl against said ratchet eel, the parts being so positioned and proportioned ti at when said pawl engages a tooth of said ratchet wheel and said arcuate plunger moves from said rst to said second position, said ratchet wheel rotates, and when said arcuate plunger is moved from said second to Said first position said ratchet wheel remains stationary, and a working member operatively connected to said ratchet wheel for rotation therewith.

9. A hydraulic ratchet Wrench comprising a tubular member, a piston disposed within the hollow portie-1 or" said tubular member adjacent one end thereof and movable between first and second positions, means for moving said piston, an end member operatively connected to said tubular member and being provided with an arcuate channel having an end in registry with th4` other end of said hollow portion, an arcuate plunger disposed in said arcuate channel and movable between first and second positions, liquid in said hollow portion for moving said arcuate plunger from said first to said second position when said piston is moved from said iirst to said second position, a cable operatively secured at one end to said piston and operatively secured at its other end to said arcuate plunger for moving said arcuate plunger from said second position to said first position when said piston is moved from said second to said first position, a ratchet wheel mounted on said end member for rotation, a pawl operatively connected to said arcuate plunger for movement therewith, said pawl adapted to engage a tooth of said ratchet wheel when said arcuate plunger moves from said first to said second position7 a double ended work member mounted for rotation with said ratchet Wheel and being movable longitudinally between two positions with respect to said wheel whereby said wrench is rendered effective for rotating said work piece in two directions by turning over said wrench and moving said working member to its corresponding position.

10. A hydraulic ratchet wrench comprising a tubular member, a piston disposed within the hollow portion of said tubular member adjacent one end thereof and movable between first and second positions, a pair of handles pivotally mounted adjacent one end of said tubular member and movable between a rst position in which the ends thereof are relatively remote and a second position in which the ends thereot' are relatively close, a piston rod connected at one end to said piston, a pair of links, each operatively pivotally connected at one end to one of said handles and operatively pivotally connected at the other end to the other end of said piston rod whereby when said handles are operated from their first to their second positions` said piston moves from its first to its second position, an end member operatively connected to said tubular member and being provided with an arcuate channel having an end in registry with the other end of said hollow portion, an arcuate plunger disposed in said arcuate channel and movable between first and second positions, liquid in said hollow portion for moving said arcuate plunger from said first to said second position when said piston is moved from said first to said econd position, a cable operatively secured at one end to said piston and operatively secured at its other end to said arcuate plunger for moving said arcuate plunger from said second position to said first position when said piston is moved from said second to said first position, a ratchet wheel rotatably mounted on said end member, a pawl operatively connected to said arcuate plunger and extending outwardly therefrom, toward said ratchet wheel, a spring operatively engaging said arcuate plunger and said pawl for biasing said pawl against said ratchet wheel, the parts being so positioned and proportioned that when said pawl engages a tooth of said ratchet wheel said arcuate plunger moves from said first to said second position, said ratchet wheel rotates and when said arcuate plunger is moved from said second to said first position said ratchet wheel will remain stationary, a double ended work member mounted for rotation with said ratchet wheel and being movable longitudinally between two positions with respect to said Wheel whereby said wrench is rendered effective for rotating said work piece in two directions by turning over said wrench and moving said working member to its corresponding position.

References Cited in the file of this patent UNlTED STATES PATENTS l491,222 Pellet Feb. 7, 1893 1,019,689 Nelson Mar. 5, 1912 1,271,365 Reynolds luly 2, 1918 2,508,568 Ellison May 23, 1950 2,517,941 Stubbs Aug. 8, 195,0 2,596,853 Helstrom May 13, 1952 

